// PostInvert.fx 
sampler samplerState; 

struct PS_INPUT {
	float2 TexCoord : TEXCOORD0;
}; 

float4 Invert(PS_INPUT Input) : COLOR0 {
	float4 col = (float4)1.0f - tex2D(samplerState, Input.TexCoord);
	return col; 
} 

technique PostInvert {
		pass P0{ 
			PixelShader = compile ps_2_0 Invert(); 
		}
}